JDBC例子

package dao;import java.sql.Connection;import java.sql.DriverManager;import java.sql.ResultSet;import java.sql.SQLException;import java.sql.Statement;public class BaseDao {//连接数据库的方法public Connection getConn() throws Exception{Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");String url="jdbc:sqlserver://localhost:1433;"+ "DatabaseName=scmng";String user="sa";String password="yuyu668668";return DriverManager.getConnection(url, user, password);}//关闭数据库的方法public void closeAll(Connection conn,Statement stmt,ResultSet rs){if(rs!=null){try {rs.close();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}}if(stmt!=null){try {stmt.close();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}}if(conn!=null){try {conn.close();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}}}}

package entity;public class Student {private String id;private String sno;private String name;private String gender;public Student() {super();}public Student(String sno, String name, String gender) {super();this.sno = sno;this.name = name;this.gender = gender;}public Student(String id, String sno, String name, String gender) {super();this.id = id;this.sno = sno;this.name = name;this.gender = gender;}public String getId() {return id;}public void setId(String id) {this.id = id;}public String getSno() {return sno;}public void setSno(String sno) {this.sno = sno;}public String getName() {return name;}public void setName(String name) {this.name = name;}public String getGender() {return gender;}public void setGender(String gender) {this.gender = gender;}}

package dao;import java.sql.Connection;import java.sql.ResultSet;import java.sql.Statement;import java.util.ArrayList;import java.util.List;import entity.Student;public class StudentDao extends BaseDao{//查询所有的方法public List<Student> findAll(){List<Student> list=new ArrayList<Student>();String sql="select * from student";Student stu=null;Connection conn=null;Statement stmt=null;ResultSet rs=null;try {conn=this.getConn();stmt=conn.createStatement();rs=stmt.executeQuery(sql);while(rs.next()){stu=new Student(rs.getString(1), rs.getString(2), rs.getString(3), rs.getString(4));list.add(stu);}} catch (Exception e) {// TODO Auto-generated catch blocke.printStackTrace();}finally{this.closeAll(conn, stmt, rs);}return list;}}

package test;import java.sql.DriverManager;import java.sql.ResultSet;import java.sql.Statement;import com.mysql.jdbc.Connection;public class TestJDBC {public static void main(String[] args) throws Exception {//1.加载驱动包Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");System.out.println("驱动加载成功！");//2.连接数据库String url="jdbc:sqlserver://localhost:1433;"+ "DatabaseName=scmng";String user="sa";String psd="yuyu668668";java.sql.Connection conn=DriverManager.getConnection(url, user, psd);System.out.println("数据库连接成功！");//3.语句String sql="select * from student";Statement stmt=conn.createStatement();System.out.println("语句获取成功");//4.结果集ResultSet rs=stmt.executeQuery(sql);System.out.println("执行查询成功！");//5.处理结果集,使用循环处理//rs.next()指针乡下移动一条语句，如果到达最后一条后面，则结果为FALSE，循环结束while(rs.next()){System.out.println(rs.getString(1)+"\t"+rs.getString(2)+"\t"+rs.getString(3)+"\t"+rs.getString(4));}//6.关闭结果集rs.close();//7.关闭语句stmt.close();//8.关闭连接conn.close();}}